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County Code
Ada 1A
Adams 2A
Bannock 1B
Bear Lake 2B
Benewah 3B
Bingham 4B
Blaine 5B
Boise 6B
Bonner 7B
Bonneville 8B
Boundary 9B
Butte 10B
Camas 1C
Canyon 2C
Caribou 3C
Cassia 4C
Clark 5C
Clearwater 6C
Custer 7C
Elmore E
Franklin 1F
Fremont 2F
Gem 1G
Gooding 2G
Idaho I
Jefferson 1J
Jerome 2J
Kootenai K
Latah 1L
Lemhi 2L
Lewis 3L
Lincoln 4L
Madison 1M
Minidoka 2M
Nez Perce N
Oneida 1O
Owyhee 2O
Payette 1P
Power 2P
Shoshone S
Teton 1T
Twin Falls 2T
Valley V
Washington W
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